Auxiliary circulating tube for boilers



NOV. 24, 1931. WADE AUXILIARY CIRCULATING TUBE FOR BOILERS Filed Nov.

2 Sheets-Sheet l NOV. 24, 1931. WADE AUXILIARY QIRCULATING TUBE FOR BOILERS 2 Sheets-Sheet 2 Filed Nov. 4. 1929 Patented Nov. 24, 1931 UNITEDFYS'TATES PATENT OFFICE EVAN a. winner OAK PARK, ILLINOIS AUXILIARY cracumi'rme TUBE FOR BOILERS,

Application filed November 4, 1929. Serial No. 404,555.

the lower rear'water leg or the front water leg or mud ring as a means of developing uniformity of temperature throughout the boiler. Y

/ The invention proceeds upon'the'principle of and resides primarily incombining auxiliary tubes with water tubes extending through the firebox of a boiler, for instance, the tubes commonly used for? supporting the l 2 fire arch, in such a manner that water issuing from the firebox tubes, and'whlch'ordlnarily enters the rear water leg of the boiler, will be directed upwardly and forwardly across the crown sheet of the firebox, there I to be discharged upon and distributed over said crown sheet if the boiler level is below said crown sheet, or discharged forwardly through ends of said tubes to promote circulation if the water level is normal; orsaid auxiliary tubes being made to continue'to conduct water forwardly until it reaches the area immediately in rear of the forward flue sheet; or, being provided with discharge openings over the crown sheet and'end openings atthe flue sheet, said auxiliary tubes -may discharge at both places and'thereby both protect the crown sheet and promote circulation at the forward end of the boiler alternatively, according to the level of the water, or simultaneously as may be desired.

The said auxiliary tubes are made to serve the still further function,-if desired, of drawing-water from the relatively inert region of the rear water leg around the fire door.

The invention consists generically in a boiler equipped with tubing combined in a manner to function in accordance with the principle stated. It further consists in certain novel features of construction whereby the tubing may be assembled in the function- Figure 6 is a rear elevation al relationship stated, particular provision being made for access to the tubing for cleaning it when required and, in some forms of the invention, for rendering the auxiliary tubes'easily separable from the. tubes which induce the circulation.

In the accompanying drawings,'in which thegprefer-redk and several modified embodiments of the invention are shown byway of illustration l v Figure 1 is a verticallongitudinal section through the firebox and adjacent portions of a locomotive boiler'in whichoneform of the present invention is installed. 7

Figure '2 is a section on the line 2:11-20!) of Figure 1 looking downward.

8 Figure 3 is a sectional detail view showing one method of assembling an auxiliary tube with a tube thatiinduces the circulation. Figure 4 is a section onthe line4w-4ar of Figure 3. 1

Figure 5 is a vertical longitudinal section through a firebox and boiler (the intermediate portion of the boiler being omitted) showing a modified construction of auxiliary tube adapted to deliver waterto the forward flue sheet area'of the boiler, as' well as over the crown sheet, and todraw water from the bottom 'of the rear leg of the boiler. of parts shown in Figure 5 and Figures 7 and 8 are detail views showing in vertical longitudinal section and in rear elevation a'modified means for releasably connecting an auxiliarytube and a firebox tube. Referring to Figures 1 to 4 inclusive, A represents a portion of a locomotive boiler, B the firebox, and C fire tubes employed in connection therewith. Firebox B is provided in a well known manner with tubes 1 supporting a fire arch D, which tubes lead from. a relatively low level in the boiler leg E rearwardly upwardly to points 2 in the rear wall F of the firebox, so that water entering the tubes 1 and becoming heated, will flow upwardly and discharge. 'Heretofore, water issuing from tubes 1 has been released directly into the rear water leg G of the boiler, whence it could rise and pass forwardly over the bringing a constant supply of water into the tubes 1 to save them from burning but improving the general circulation of the boiler. But when through carelessness or unavoidable cause the water level of the boiler is lowered sufficiently to leave the crown sheet H exposed, circulation thus induced by the tubes 1 would merely flow forwardly through the side legs I of the boiler in compensating for water entering said tubes, thus leaving the crown sheet H to be burned or overheated in a. manner to permit it to fail under the internal pressure of the boiler and cause an explosion.

In order to meet the hazard of low water effects upon the crown sheet H, the present invention employs, in combination with tubes such as 1, auxiliary tubes 3 fitted at their lower ends over the discharge openings 2 of the tubes 1, and leading thence upwardly and forwardly across a sufficient proportion of area of the crown sheet H to cause the water flowing through tubes 1 to be distributed over or flow across the crown sheet in a manner to preserve the latter from destruction. To adapt the auxiliary tubes 3 to function as stated. they are provided with perforated sections 4: and. to fix the latter against displacement relatively to the crown sheet, any suitable means such as one or more racks 5 may be employed.

Auxiliary tubes 3 are preferably releasably secured imposition over the ends 2 of the tubes 1 in order to afford accessto the tubes 1 when it becomes necessary to clean them. One convenient means for accomplishing th1s end consists in a screw 6 threaded in a plug 7 that closes the hand-hole in the rear wall of the boiler, and bearing at its forward end 8 against the capping end 9 of the tube 3 in a manner to force the latter to a sufficiently firm seating over the end 2. Obviously, the connection between the capping end 9 of auxiliary tube 3 and the rear boiler plate through which tube 1 extends need not be absolutely water-tight it is merely necessary that it control the main body of the water delivered from tube 1 and cause it to be driven, under the pressure within tube 1, upward and for ward to the desired point of discharge. With this arrangement, when it becomes necessary to clean a tube 1, it is merely necessary to remove the plug 7 with the screw 6. the screw having been first eased from pressure against the capping end 9, and then swing the depending section of tube 3 to one side sufliciently to admit the blasting or other cleaning tool to tube 1.

If desired, the lower capping end of auxiliary tube 3 may be releasably secured over the end 2 of tube 1 through the means shown in Figures 7 and 8, where 10 represents a socket rack suitably riveted as at 11 to the rear boiler plate, while the capping end 9a of auxiliary tube 3a is formed with an engaging flange 12 fitting said rack in a manner to hold the inner face of the flange in approximately water-tight relation to the boiler plate, the forwardly extending section 4a of the auxiliary tube 3a being, in this instance, supported vertically by one or more racks 5a with freedom of the tube to be lifted therefrom when it becomes necessary to release the capping end 9a and expose the open end 2 of tube 1 to access through the hand-hole 7 a.

As shown in Figures 5 and 6, it is not necessary that the auxiliary tube, here designated as 36, be releasably secured over the open end 2 of tube 1; instead, it may be permanently secured in position by means such as rivets 13, in whichcase, hand-hole 14 will be provided in the rear wall of the capping end 97) of said auxiliary tube in alignment with the hand-hole 7a in the rear wall of the boiler. so that by removing plugs 7 and 15 access will be afforded to the interior of tube 1. In this form, any suitable supporting rack such as shown at 5?) may be employed for the horizontal sections of the auxiliary tubes.

As also shown in Figures 5 and 6, auxiliary tubes 3?) may be provided with extensions 16'reaching down into the lower portion of the rear water leg G in such a manner that upward flow will be induced through these extensions 16, thereby improving the general boiler circulation through the section G as well as along the side legs I leading thereto.

As illustrated at 16a in Figures 7 and 8, ex tensions corresponding to the extensions 16 of Figures 5 and 6 may be employed in those forms of the auxiliarv tube in which the canping end 9a is releasably held in position quite as Well as in the form shown in Figures 5 and 6, in which the capping end is riveted to the rear firebox wall.

As also shown in Figure 5, the horizontal sections 172 of the auxiliary tubes 3?), in addition to having perforations 4a: through which they release water upon the crown sheet H. may be developed to suflicient length. to provide further extensions 46 reaching substantially the full length of the interior of the boiler and discharging at 4m in rear of the flue sheet K, thereby causing to take place at the extreme forward portion of the boiler, a circulatory movement of water that compensates for the. rearward, upward flow through firebox tubes 1, and further improving the general circulation of the boiler and consequently developing greater uniformity of temperature throughout the boiler.

While the description has dealt largely with single tubes in describing the relationship between the auxiliary tube and the the box tube, it is to be understood that any desired number of firebox tubes and a corresponding number of auxiliary tubes are to be used.

In addition to the primary aims realized by the use of this invention, it has the im portant efiect of guarding against false readings in the gauge-glass placed at the rear end of the boiler. Heretofore, on occasions it has been found that strong ebullition through the firebox tubes causes them to discharge in the rear vertical water leg of the boiler at a rate that indicates a materially higher water level in the gauge-glass than that which exists throughout the boiler. By means of the present invention, water discharged by the firebox tubes is conducted to points sufliciently remote from the rear water leg to cause a very much more nearly uniform water level throughout the boiler than when the firebox tubes are used alone. This is true in an appreciably advantageous measure even when the protecting tubes do not extend beyond the crown sheet, and it is particularly true when they extend to the vicinity of the tube. sheet which constitutes the front wall of the boiler; and this is true notwithstanding escape openings in the portions of the safety tubes which overlie the crown sheet.

I claim:

1. In a boiler having a firebox, a firebox arch tube communicating at its ends with the boiler at the inside firebox sheet, and an auxiliary tube located wholly within the pressure confine of the boiler and having one end in detachable communication with the upper end of said firebox tube and leading across and discharging water at a plurality of points upon the crown sheet.

2. In a boilerhaving a firebox and a crown sheet, a flow-inducing tube located in the firebox, terminating at the inside firebox sheets and communicating at its ends with the boiler, and an auxiliary tube located wholly within the pressure confines of the boiler, communicating with the discharge end of the flow inducing tube and constructed and arranged to extend across and discharge water at a plurality of points upon the crown sheet and also at a point beyond the crown sheet.

3. In a boiler having a firebox, a tube receiving water at one end from one portion of the boiler, extending across the firebox and discharging water into another portion of the boiler, and an auxiliary tube secured over the discharge end of the tube first named, leading therefrom to a remote portion of the boiler, and having an intake extension beyond its point of communication with the firstnamed tube extending to and drawing water from another remote portion of the boiler.

4. In a boiler having a firebox and a water leg adjacent a wall of said firebox, a firebox tube communicating at one end with a boiler, extending across the firebox and discharging at its other end into said water leg, and an auxiliary tube communicating with the discharge end of said firebox tube and 65 leading to and discharging into the boiler at a place remote therefrom; said auxiliary tube having an extension below the discharge end of the firebox tube reaching into and drawing water from the lower portion of said water leg.

5. In a boiler having a firebox, a crown sheet and a front flue sheet, a flow-inducing water tube receiving water at one end from the boiler and discharging at its other end into the boiler, said tube having its ends terminated at the inside firebox sheets, and an auxiliary flow tube secured over the discharge end of said flow-inducing tube and leading thence across the crown sheet and to a point adjacent the flue sheet; said auxiliary tube being wholly within the pressure confines of the boiler and constructed to discharge water above the crown sheet and also adjacent the flue sheet.

Signed at Chicago, Illinois, this 1st day of November, 1929.

EVAN H. WADE. 

